Various epidemiological studies have proven that sleep apnea is highly prevalent amongst sleep related conditions and affects between 4-6% of males and 2-4% of females in the general middle-aged adult population.
The main problems related to sleep apnea include significant reduction in quality of life, arterial hypertension and the development of cardiovascular and cerebrovascular diseases.
Obstructive sleep apnea is therefore one of the most widespread and worrying sleep conditions.
The most extensive methods known to date for treating obstructive sleep apnea include:
US005245995A: A device named CPAP, consisting of a turbine that transmits a predetermined pressure via a nasal mask, adapted to the subjects face and fixed with a harness, with which the circuit is closed.
The device is effective in terms of continuously treating the illness, however presents various limitations:                Nasal congestion and/or obstruction. Nasal congestion is the most common and treatment depends on the cause behind it. It usually arises as a result of edema and inflammation of the nasal mucus.        Irritated skin. This occurs in the area that comes into contact with the CPAP mask.        A dry throat. This is caused by water being lost from the soft palate, as a result of snoring and apnea and the air flow from the device itself. In order to be corrected, it is necessary to install a humidifier/heater connected to the CPAP.        Noise. In addition to noise produced by the CPAP, which goes unnoticed after the first few weeks, patients and their companions complained of tonality changes between inhalation and exhalation produced in the mask.        Cold. This is particularly significant in cold areas and houses without heating, where in winter, air from the CPAP may enter the VAS at 15° C. or lower (the temperature recommended for sleep being around 19° C.).        
Surgical techniques: these involve generally aggressive surgical techniques, which are reserved in many cases for when the CPAP does not work or for patients who reject it before looking into it further. It requires very precise prior anatomical exploration and must be carried out by experienced surgeons. The ill person must be informed of the chances of success exhaustively and may require more than one intervention.
Electric stimulation: The first research on electric stimulation treatments for obstructive sleep apnea was carried out in the 1980s, when Dr. Miki's team in Japan carried out various experiments on this usage.
Since then, several pieces of apparatus have been produced, which have attempted to apply principles related to electric stimulation in order to prevent the collapse of the upper airways by means of contracting the muscles involved. Some are internal, whilst others are external.
One device implanted into the subject internally is:
US006345202B2, which proposes a method for treating apnea using micro-electrodes implanted into strategic places inside a patient. They are controlled wirelessly by an external transmitter, in order to stimulate the muscular and nerve tissue in a constructive way, which helps to open the airways blocked.
External Devices include:
US 2008/0021506A1, which uses electrodes fitted to the surface, to prevent snoring and sleep apnea.
US 2006/0145878A1, which proposes a method and system for fighting apnea, wherein the subject is woken up.
WO 2006/054359, which proposes electrical timulati by means of applying electrodes in the jaw portion of a patient, in order to prevent sleep apnea. It therefore applies electrical signals repeatedly during the night, without considering the state of obstruction in the upper airways.
One limitation common to all the above proposals is the lack of regulation. They do not facilitate automatic adjustment, in order to adapt to the morphological characteristics and the intensity level of apnea episodes of each patient.
The same goes for the CPAP device, wherein prior adjustment is required, thus increasing the costs of installing the apparatus for each patient considerably. It is currently substituted by an automatic graduation CPAP system known as the APAP (Roldán N et al. 2008).
The apparatus and method described below compensates for the deficiencies identified in the state of the art and constitutes a significant technological advancement, since it facilitates self-regulating detection and treatment, in order to adapt to a patient's morphology. It uses the minimal electric shock required in terms of both frequency and intensity in the muscles involved. Furthermore, it facilitates follow-up and control of the evolution of the condition.